DIY Lighting Project (LED Strips)

Don't you really need to know the power used per LED, then you can work out the number of LEDs in the length you use and hence the power required?

I light my whole average sized sitting room adequately using three compact fluorescent light bulbs each of 23 watts for a total of 69 watts. LEDs are more efficient than fluorescent lighting. It seems to me therefore that only a relatively small number of  LEDs should be more than enough to light a normal sized tank. My aim in changing to LEDs is to save money on electricity, not to make the lights any brighter. Am I missing something? Wouldn't a 5 metre length be enough for an enormous tank? The seller said that the 5 metre length I bought would use 72 watts total. That would have to be divided among several tanks to make it more economical than the existing tubes.

I have one flexible "rubbery" strip which is 1.2 metres length and has 120 LEDs, plain old 3528 single ones. It is constructed such that it bends round corners easily without twisting, unlike the flat strips that are sold in 5 metre lengths. It easily provides enough light for a 60 litre/60 cm. tank (glued internally in a U shape). It uses 9 watts, less than a third of the consumption of the two 15 watt tubes there before, while providing at least as much light and cost just £8.99 with power supply. It's a pity that 1.2 metres seems to be the longest length available, longer and you can only get the flat tape type. I have 3 more 60 cm tanks which I plan to light in the same way. I may add a red strip later to enhance colours. The electricity savings should be considerable, after all 12 hours a day @ 30w = 0.36 kwh/day while the same @ 9w = 0.108 kwh/day. If I can do the same sort of thing with the other 8 tanks I have that use fluorescent tubes then I can afford to run a couple more tanks!! I'm still working out the best way to use the flat strips on the larger tanks.

Don't you really need to know the power used per LED, then you can work out the number of LEDs in the length you use and hence the power required?

I light my whole average sized sitting room adequately using three compact fluorescent light bulbs each of 23 watts for a total of 69 watts. LEDs are more efficient than fluorescent lighting. It seems to me therefore that only a relatively small number of  LEDs should be more than enough to light a normal sized tank. My aim in changing to LEDs is to save money on electricity, not to make the lights any brighter. Am I missing something? Wouldn't a 5 metre length be enough for an enormous tank? The seller said that the 5 metre length I bought would use 72 watts total. That would have to be divided among several tanks to make it more economical than the existing tubes.

I have one flexible "rubbery" strip which is 1.2 metres length and has 120 LEDs, plain old 3528 single ones. It is constructed such that it bends round corners easily without twisting, unlike the flat strips that are sold in 5 metre lengths. It easily provides enough light for a 60 litre/60 cm. tank (glued internally in a U shape). It uses 9 watts, less than a third of the consumption of the two 15 watt tubes there before, while providing at least as much light and cost just £8.99 with power supply. It's a pity that 1.2 metres seems to be the longest length available, longer and you can only get the flat tape type. I have 3 more 60 cm tanks which I plan to light in the same way. I may add a red strip later to enhance colours. The electricity savings should be considerable, after all 12 hours a day @ 30w = 0.36 kwh/day while the same @ 9w = 0.108 kwh/day. If I can do the same sort of thing with the other 8 tanks I have that use fluorescent tubes then I can afford to run a couple more tanks!! I'm still working out the best way to use the flat strips on the larger tanks.

The biggest mistake that people can make is trying to use a watt by watt comparison when converting to LEDs. The problem is there are many different types, each producing light more or less efficiently than the others. For example, the 3528 LEDs you mention are pretty dim and inefficient. The 5m/72watt strips you mention will be 5050 chips, which are still fairly inefficient, but produce the most light per £. There are now the 5630 LEDs that are more expensive to buy initially, but are brighter than the 5050's and more efficient to run (so cheaper long term). Comparatively, a 1m strip of each type will output approximately 216, 756, and 1536 lumens respectively, but use 4.8, 14.4, and 24 watts for that light.

To compare to an iridescent light, such as your compact fluorescents, you need to be looking at the light produced by both types of light (usually in lumens). Compact fluorescents are already pretty efficient lights. LEDs will save a bit on the running cost, but also have the advantage of not having to warm up, are much more controllable, longer life etc.

If the light in your 60 litre aquarium outputs 750 lumens, for example (which is what a single 24" 20w Hagen Power-Glo produces), you would need either of the below for the equivalent light output in LEDs:

3528: 3.5 metres - 756 lumens - 16.8 watts
5050: 1 metre - 756 lumens - 14.4 watts
5630: 0.5 metres - 768 lumens  - 12 watts.

I do understand, but finding output in lumens for tubes is difficult. I don't know how a Hagen Power-glo tube compares with the very cheap ones I buy (£2 - £3 each) but I wouldn't want an 18000k tube anyway, those were originally intended for marine tanks. All I can say is that with the set up I describe, superficially at least the tank is just as brightly lit as with the two tubes. In addition, the plants I have are thriving just as well as ever. As I've noted before I only use easy plants as my interest is in providing a good habitat for the fish rather than creating a decorative feature.

I do have a 5m roll of 5630 leds and a 72w power supply. I was planning to cut this into strips of different lengths to share among three tanks which are adjacent to each other, using the one power supply for all three tanks but am still deciding how best to connect all the power leads etc. There are two 80 cm tanks, where I was planning to put two 70 cm. strips in each and one 60 cm. tank where I want two 50 cm. strips. That would make a total of 380 cm. used in total which should be well within the capacity of the power supply. This would mean splitting the power from the supply three times initially, then each of those splitting into two.

According to your figures 0.5 metres of 5630 uses 12 watts, which would mean 24 watts/metre which is twice what is generally quoted so I assume an error? If so, in the 60 cm. tank I would have 1 metre of LEDs, using 12 watts and producing 1536 lumens, while in the 80 cm tanks it would be 1.4 metres using about 17 watts and producing 2150 lumens. Have I got that correct? Any corrections gratefully accepted...........

The power-glo seems to be an middle ground for light output, which was why I picked it, some are lower and some are much higher (for example the sun-glo). The lumens may be on the packaging of your cheap tubes, more and more companies seem to be adding it these days? The 1.2 metre strip you have with 144 3528 chips will be outputting around 518 lumens, which is pretty close to an Aqua-Glo tube, so if you mainly keep low-tech plants I'm sure they'll do fine.

I don't think you'll have any issues wiring up your power supply. It all sounds straight forward. 3.8 metres would draw 91.2 watts, so you'll be leaning on your power supply a fair bit.

I have seen so much discrepancy when it comes to 5630 LEDs, but after doing a lot of research I've found a lot of sellers to be misleading. 24 watts per metre is pretty accurate based on datasheets from the chip suppliers. I've seen a lot of sellers listing them at 14.4 watts per metre, which has probably been copied and pasted from a 5050 strip, and I've also seen 7.2 watts per metre, which is actually the 5630's rating per foot (30cm). I think part of the low-balling on the power usage could be simple copy and paste mistakes, the other could be so that the seller can either ship with a smaller power supply or you think you need a smaller/cheaper power supply so as not to scare off potential buyers.

In the 60 cm. tank you would have 1 metre of LEDs, using 24 watts and producing 1536 lumens, while in the 80 cm tanks it would be 1.4 metres using about 33.6 watts and producing 2150 lumens.

I've added a calculator at the bottom of this page for working out the power usage, and another calculator in the middle of this page to calculate LEDs based on the lumens emitted by any current lighting. Using the latter calculator, you may be able to spread the 5 metres of strips you have around more aquariums, making your power usage even more efficient.

Richard I'm currently running about 3.5M of 5630s in my 81cm tank using an underpowered 12W power supply.

The LEDs are significantly dimmer than they should be, but are still almost bright enough.

You may very well find that running with an underpowered DC adaptor you will save money and still be satisfied with the brightness.

Thanks Darren, very interesting. It does appear that there is very little difference in practice in terms of power use between different LEDs for a given light output. One could simply use more of the lower output types to get the same light output, give or take a bit.

If I follow the plan I outlined with the 5630 type, there will be very little saving in electricity compared to using tubes and so I'll reconsider. In fact two of my 60 cm. tanks are lit with a single 15w tube and so your figure of 24w with 5630 LEDs would not be economic though I expect the tanks would be much more brightly lit.

No problem, glad I can help

You're right, you can just use more or less LEDs to get the same light output, the limiting factor would be the space in the aquarium's hood. However, I think there is a fair difference in energy usage. For the example earlier there was 4.8 watts difference, and that's based on a small aquarium. The difference gets larger as the lumens increase. You also have to factor in the lifespan, where LEDs should last much longer than the incandescent equivalent if they're set up to run within their tolerances (mainly not allowed to overheat - the 5630's should ideally be mounted on an aluminium plate to dissipate the heat).

True, but if you change your plan slightly you could still save. You said you're happy with the 1.2m strip in one of your 60cm tanks, which was calculated to be emitting 518 lumens. If we aimed for 600 lumens (which is half way between the Aqua-Glo and Flora-Glo tubes), you would only need to use a 40cm length of 5630 LEDs, which would use 9.6 watts of power. Using the same model, the 80cm tank would need around 800 lumens, which equates to 60cm of 5630 LED strip, which uses 14.4 watts. That would be 38.4 watts for all 3 tanks.

It may not be much of a problem depending on the LED's height above the water. They tend to have a pretty wide 120 degree light angle, so 10cm in from the edge of the hood may not equate to much at the surface. Gimmie a sec and I'll work it out.

***** Update *****

Based on 11.5 cm in (10 cm plus 1.5cm for the circuit board before the LED), the light will hit the side of the aquarium 6cm down.

Any updates on these lighting projects? I understand why we don;t see much of @Extreme_One these days so I don't expect an immediate response 

I ordered a metre of cool white 5630 today. I will order a TC420 after my holiday this month, I have an unused 12v power supply amongst other cables and stuff in the garage. It's a 5 amp unit rated at max 70 or 84 watts depending on what google result you find, unfortunately the wattage isn't marked.

I will do some playing around with the led strip and so long as it works I'll order a metre of blue strip to go with it. I plan to remove the flourescent unit from my tank and use 2x 50cm White led strips and 2x 50cm blue led strips wired in parallel, arranged across the glass shelf the existing unit sits on.

I'll let you know how I get on. 

...I have an unused 12v power supply amongst other cables and stuff in the garage. It's a 5 amp unit rated at max 70 or 84 watts depending on what google result you find, unfortunately the wattage isn't marked.

If the output from your 12V power supply is 5A, the the output power is 60Watts. Voltage x Current = Power

Hey Paddy,

I hope it all goes well. If you need any help with the LEDs or the TC420 just stick a reply on here (I still get the notifications or drop me an email on my web site http://www.TC420.net and I'll do what I can to help.

My projects are on hold at the moment, partly because I've decided to go saltwater with the 6' tank and also needing to save up for a new fridge freezer :/

All the info for strip LEDs and the TC420 unit it's self is on my web site, and I has all the information to get it working with high power LEDs, I'm just waiting till I build it myself so that I can a) proove the concept and b) take detailed photos to make things easier.

Fiona, there is a guide on my web site for LEDs, let me know if it's too complicated and I'll see what I can do to make it easier to understand. I'd love the feedback

Good luck with all your projects